Need some help setting up wordpress multi-site Nginx

Hi, i have setup wordpress multi-site following this tutorial https://www.digitalocean.com/community/tutorials/how-to-set-up-wordpress-multisite-with-nginx-on-ubuntu-14-04

i installed it on sub-directory by adding the following code.

    if (!-e $request_filename) {
        rewrite /wp-admin$ $scheme://$host$uri/ permanent;  
        rewrite ^(/[^/]+)?(/wp-.*) $2 last;                     
        rewrite ^(/[^/]+)?(/.*\.php) $2 last;                   
    }

everything working perfectly but when i try to change tagline or permalink of my site 2 & 3 it dont allow me.

secondly, wordpress network menu is visible to all the sites admin panel. even for 2nd & 3rd site. is there any way to disable network menu for the 3rd site? so that from that sites wp-admin only can manage that sites settings and not see entire network.

lastly, from the main site, example.com/wp-admin i cant find domain menu under tools but from 2nd & 3rd site i can find them. is it normal?

another thing i must add, i cant add following marked code in location ~ .php$

location ~ \.php$ {
        try_files $uri =404;
        include fastcgi_params;
        fastcgi_pass unix:/var/run/php5-fpm.sock;
    }

it gives me sytax error saying try files duplicate. is it because i have this code in virtual host?

 location / {
        try_files $uri $uri/ /index.php?$args;
    }

thanks in advance.